Vi-agglutinin, active cutaneous anaphylaxis and protective responses (ED50) of three mouse strains (CFW, NIH, and Balb/cAnN) to acetone-inactivated typhoid vaccine and soluble Vi antigen were compared. Seven days after immunization with either typhoid vaccine or Vi antigen the three strains of mice differed with respect to Vi-antibody titers. Significant differences were observed in the protective responses. Each mouse strain was significantly better protected by the intraperitoneal than by subcutaneous route of immunization. Active cutaneous anaphylaxis was more pronounced in showing strain differences in response to Vi antigen. The serological responses to Vi antigen of the strains of mice did not correlate with their protective response.
Vi antibody response of rabbits varied depending on whether Vi antigen was administered in particulate or soluble state. Vi antigen in particulate form induced hemagglutinins, bacterial agglutinins, and passive cutaneous anaphylaxis (PCA) antibodies, whereas soluble Vi antigen induced only hemagglutinins. Guinea pigs passively sensitized with antisera against particulate Vi antigen gave PCA reactions when challenged with either soluble or cellular Vi antigen; antisera against soluble Vi antigen were negative for PCA. The specificity of PCA was demonstrated by its dependence on the Vi concentration and by absorption of PCA activity from antisera with V-form cells of
Salmonella typhosa
.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.